#include <bits/stdc++.h>
using namespace std;

class Solution {
    int dx[4] = {0, 0, -1, 1};
    int dy[4] = {-1, 1, 0, 0};
    int m, n, prevcolor;

public:
    vector<vector<int>> floodFill(vector<vector<int>>& image, int sr, int sc, int color) {
        if (image[sr][sc] == color)
            return image;
        m = image.size(), n = image[0].size();
        prevcolor = image[sr][sc];
        dfs(image, sr, sc, color);
        return image;
    }

    void dfs(vector<vector<int>>& image, int i, int j, int color) {
        image[i][j] = color;
        for (int k = 0; k < 4; k++) {
            int x = dx[k] + i;
            int y = dy[k] + j;
            if (x >= 0 && x < m && y >= 0 && y < n && image[x][y] == prevcolor) {
                dfs(image, x, y, color);
            }
        }
    }
};